This proposal is for a K01 Mentored Research Scientist Development Award. The applicant is an epidemiologist and developing investigator at the Cornell Advanced Center of Interventions and Services Research (ACISR). Her goal is to develop into an independent investigator who focuses on the clinical epidemiology of late life depression, specializing in strategies to bridge the disciplinary gap between methodology and clinical substance with the aim to reduce the burden of late life depression. Her approach to achieving this goal is to learn advanced methodology in order to address complex clinical questions on the onset, course, and outcomes of geriatric depression, and to understand how interventions can modify the decline in health associated with this course. The proposed training and research plans are designed to complement and reinforce each other. The specific training objectives are to learn about: 1) advanced research methods related to psychosocial and environmental factors of psychopathology, 2) clinical concepts about the relationship of cardiovascular/cerebrovascular disease to psychopathology, cognition and depression, 3) clinical trials research, and 4) complex population-based sampling and population-based randomized intervention studies. The research is designed to further our understanding of two leading-edge questions in geriatric psychiatry The first project addresses one of the etiological theories of geriatric depression, the 'Vascular depression" hypothesis, and asks: To what extent do indices of peripheral and central vascular disease act as risk factors for depressive symptoms in older adults? The second investigates the course and outcomes of depression, and asks: To what extent do depression-interventions modify the relationship between depression and disability over time in older adults? The research will be conducted using two established population-based, longitudinal data sets, each offering an unique opportunity to test hypotheses for which appropriate data are rarely available: the Cardiovascular Health Study (CHS) and the Prevention of Suicide in Primary Care Elderly: Collaborative Trial (PROSPECT). The conceptual and methodological challenges of using these data to test hypotheses related to the complexities of geriatric depression will reinforce the applicant's formal training.